There are six houses which were named after persons who contributed to Mengo Senior School. Upon admission into the school, every student is placed in a house in which they do their co-curricular activities. Each house is headed by a house patron or patroness who coordinates all house activities. House activities include M.D.D and Sports competitions among others.
Houses have their particular colours as shown by the house T-shirts.
The Houses are:
1. Armitage (Red).
The House was named after Rev. B.A. Armitage (Headteacher 1966 – 1972). The current house teacher is Mr. Kiggundu Charles.
2. George (Pink).
The House was named after Mr. Vergise George who was the school’s headmaster from 1972 – 1985. The current house teacher is Ms. Namutebi Alex.
3. Kennedy (Yellow).
It was named after JF kennedy, former president of the USA. The current House teacher is Mr. Ssettabi Joshua.
4. Luboyera (Green).
This house was named after Rev. F.B. Luboyera (Headteacher 1913 – 1929). The current house teacher is Mrs. Katimbo Esther Nabbembe.
5. Nsubuga (Orange).
This house was named after Bishop Nsubuga. The current house patron is Mrs. Mulumba Patricia.
6. Sempa (Blue).
This house was named after Rev. Y.B. Sempa (Headteacher 1929 – 1965). The house is currently under the leadership of Mr. Kyosabira Julius.